Genetic variation and cryptic lineage diversity of the Nigerian red-headed rock agama Agama agama associate with eco-geographic zones.

Nigeria is an Afrotropical region with considerable ecological heterogeneity and levels of biotic endemism. Among its vertebrate fauna, reptiles have broad distributions, thus, they constitute a compelling system for assessing the impact of ecological variation and geographic isolation on species diversification. The red-headed rock agama, Agama agama, lives in a wide range of habitats and, thus, it may show genetic structuring and diversification. Herein, we tested the hypothesis that ecology affects its genetic structure and population divergence. Bayesian inference phylogenetic analysis of a mitochondrial DNA (mtDNA) gene recovered four well-supported matrilines with strong evidence of genetic structuring consistent with eco-geographic regions. Genetic differences among populations based on the mtDNA also correlated with geographic distance. The ecological niche model for the matrilines had a good fit and robust performance. Population divergence along the environmental axes was associated with climatic conditions, and temperature ranked highest among all environmental variables for forest specialists, while precipitation ranked highest for the forest/derived savanna, and savanna specialists. Our results cannot reject the hypothesis that niche conservatism promotes geographic isolation of the western populations of Nigerian A. agama. Thus, ecological gradients and geographic isolation impact the genetic structure and population divergence of the lizards. This species might be facing threats due to recent habitat fragmentation, especially in western Nigeria. Conservation actions appear necessary.

Construction and Evaluation of a Self-Calibrating Multiresponse and Multifunctional Graphene Biosensor.

Recently, many studies have been focused on the development of graphene-based biosensors. However, they rely on one type of signal and need to be calibrated by other techniques. In this study, a nonenzymatic graphene-based biosensor has been designed and constructed. Its ability to detect glucose and Escherichia coli by three different types of signals has been investigated. For its preparation, dopamine-functionalized polyethylene glycol and 2,5-thiophenediylbisboronic acid were conjugated onto the surface of graphene sheets by nitrene [2 + 1] cycloaddition and condensation reactions, respectively. Multivalent interactions between boronic acid segments and biosystems consequently increased the quantifiable fluorescence emission and UV absorption of dopamine segments. Additionally, changing the electrochemical behavior of the functionalized graphene sheets was possible and resulted in a measurable output signal. Conjugation of mannose onto the surface of the biosensor improved its magnitude of signals and specificity for sensing E. coli in a complex medium. The efficiency and accuracy of each signal was monitored by others, which resulted in a real-time self-calibrating biosensor. Taking advantage of the versatility of the three different indicators, including florescence, UV, and electrochemistry, the functionalized graphene sheets have been used as self-regulating biosensors to detect a variety of biosystems with a high accuracy and specificity in a short time.

Gel- and Solid-State-Structure of Dialanine and Diphenylalanine Amphiphiles: Importance of C⋠⋠⋠H Interactions in Gelation.

To investigate the role of the capping group in the solution and solid-state self-assembly of short peptide amphiphiles, dialanine and diphenylalanine have been linked via the N-terminus to a benzene (phenyl) and 3-naphthyl capping groups using three different methylene linkers; (CH2 )n , n=0-4 for the benezene and 0, 1 and 2 for the naphthalene capping group. Atomic force microscopy (AFM), oscillatory rheology, circular dichroism (CD), and IR analysis have been employed to understand the properties of these peptide-based hydrogels. Several X-ray structures of these short peptide gelators give useful conformational information regarding packing. A comparison of these solid state structures with their gel state properties yielded greater insights into the process of self-assembly in short peptide gelators, particularly in terms of the important role of C⋅⋅⋅H interactions appear to play in determining if a short aromatic peptide does form a gel or not.

Angiotensin-converting enzyme (ACE) serum levels and gene polymorphism in Egyptian patients with systemic lupus erythematosus.

OBJECTIVES: To investigate the association of angiotensin-converting enzyme (ACE) gene polymorphism and serum ACE level among Egyptian SLE patients and its relation to disease activity parameters. SUBJECTS AND METHODS: We enrolled 50 Egyptian female systemic lupus erythematosus (SLE) patients and 29 healthy controls. Measurement of serum ACE level was done using ELISA, and the ACE genotype was determined by polymerase chain reaction using genomic DNA from peripheral blood. RESULTS: A significant difference was found in ACE genotypes between SLE patients and controls (χ(2 )= 7.84, p = 0.02). The frequency of ACE DD versus (DI and II) genotypes was significantly higher in SLE patients compared with controls (χ(2 )= 5.57, p = 0.018 and OR for risk of SLE was 3.1 with 95% confidence interval: 1.198.06). Mean serum ACE level was significantly higher in the SLE group compared with controls (p = 0.006). Subjects with DD genotype had a significantly higher mean level than those with DI (p = 0.015) and II genotypes (p = 0.02). Lupus nephritis patients had a significantly higher frequency of DD versus DI and II genotypes compared with lupus patients without nephritis (Fisher's exact test, p = 0.025) and controls (χ (2) =8.74, p = 0.003). SLE patients with vasculopathy had a significantly higher frequency of DD versus DI/II genotypes compared with SLE patients without vasculopathy (Fisher's exact test, p = 0.04) and controls (χ(2 )= 9.84 and p = 0.002). Mean serum ACE level was significantly higher in the lupus nephritis and SLE patients with vasculopathy compared with controls (p = 0.008, p = 0.001, respectively). Significant positive correlations were found between serum ACE level and serum creatinine and 24 h proteinuria (p = 0.03, 0.009, respectively). SLE patients with DD genotype had a statistically significant higher mean SLEDAI score than those with (DI/II) genotypes (p = 0.02). Significant positive correlation was found between serum ACE levels and SLEDAI scores (p = 0.04). CONCLUSION: ACE genotype and subsequently serum ACE level could be associated with the disease activity of Egyptian SLE patients; in addition, ACE deletion polymorphism might be used as one of the predictive factors for the activity of SLE. Further studies on a larger number of patients should be done to determine the exact prevalence of ACE gene polymorphism among Egyptian SLE patients.

[Characteristics of patients suffering from multiple sclerosis according to professional situation]. / Caractéristiques des personnes atteintes d'une sclérose en plaques selon la situation professionnelle.

AIM: To describe the health and professional status of multiple sclerosis patients of working age and to compare a group of patients in work (group T1) with a group of unemployed patients (group T2). MATERIALS AND METHODS: A case-controlled study was performed. In the course of a specific consultation with a neurologist, demographic, medical and professional data were gathering using a questionnaire. Descriptive and comparative statistical analyses were then performed. RESULTS: A total of 76 patients were included in the study: 54 were in work (group T1) and 22 were unemployed (group T2). Hence, the employment rate was 71%, with an average time since disease onset of nine years at the time of the study. Low educational level (p=0.02), disease progression (p=0.0001), the presence of motor symptoms (p=0.01), cerebellar symptoms (p=0.02) or cognitive symptoms (p=0.03), a worse EDSS (p=0.0001) and a job requiring force (p=0.05) or manual dexterity (p=0.05) were found to be negative factors. Employment in the public sector (p=0.003) or large companies (p=0.03) were found to be protective factors. Access to the workplace was better for currently employed patients (p=0.03). CONCLUSION: This study shows that differences exist within the MS patient population according to the professional situation. It underlines the importance of clinical and demographics variables as determinants of differences in employment status. Not surprisingly, unemployed patients are more likely to have been classified as handicapped workers. Factors linked to work-induced constraints did not emerge from the survey because the questionnaire items were not appropriate for addressing this latter issue.

Analysis of pyridoquinoline derivatives by liquid chromatography/atmospheric pressure chemical ionization mass spectrometry.

A method using liquid chromatography/atmospheric pressure chemical ionization mass spectrometry (LC/APCI-MS) has been developed for the characterization and determination of pyridoquinoline derivatives 4,6-bis(dimethylaminoethylamino)-2,8,10-trimethylpyrido[3,2-g]quinoline, 4,6-bis(dimethylaminoethoxy)-2,8,10-trimethylpyrido[3,2-g]quinoline and 4,6-bis[(dimethylaminoethyl)thio]-2,8,10-trimethylpyrido[3,2-g] quinoline, all with potential antitumor properties. LC separation was performed on a conventional C18 column using a binary mobile phase composed of acetonitrile and 50 mM aqueous ammonium formate at pH 3. The APCI mass spectra obtained showed that proton addition giving [M + H]+ was the common mode of ionization to the amino- and thiopyridoquinolines, whereas the alkoxypyridoquinoline was identified by the main formation of the [M - (C2H3)N(CH3)2 + H]+, followed by the [M + H]+ ion. The LC separation conditions and MS detection parameters were optimized for the determination. The analytical method was also applied to the determination of these pyridoquinoline derivatives in fetal calf serum using liquid-liquid extraction with dichloromethane. Acceptable recovery values were obtained, ranging between 45 and 98%.

Unreamed femoral nailing.

Sixty one femoral fractures treated with ACE unreamed titanium nail (AIM femoral nail, ACE Medical, Los Angeles, CA) were studied. Ten patients died before bony union and three were lost to follow up. Forty eight fractures were followed up for an average of 11.2 months (4-31 months). All fractures united except one in which plating and bone grafting was performed at 6 months due to failure of progression of union. The mean time to bony union was 6.2 months. There was no implant failure but one distal interlocking bolt broke at 6 weeks. No incidence of adult respiratory distress syndrome (ARDS) was observed. Malunion was seen in one patient whereas three cases had shortening of more than 2 cm. Our results show that unreamed femoral nailing using titanium nail is a safe and effective procedure for the treatment of femoral shaft fractures.

Endurance exercise training in Guillain-Barre syndrome.

The purpose of this case study was to determine whether an individual who had residual deficits following an acute incidence of Guillain-Barre Syndrome (GBS) would experience improved physiological adaptations following aerobic endurance training. A 57-year-old man who needed the aid of a crutch for walking three years following an acute bout of GBS participated in this study. Peak work level (watts), oxygen consumption (VO2 mL/min; mL/kg.min), and ventilation (VE, L/min) were determined on a bicycle ergometer (BE), a Schwinn Air-Dyne ergometer (SAE), and an arm crank ergometer (ACE) before and after exercise training. Isokinetic leg strength measured using a dynamometer and total work capacity in watts using BE were also determined before and after training. The subject trained for 16 weeks at an approximate frequency of 3 days/week, an average duration of 30 minutes, and an average intensity of 75% to 80% of pretraining peak HR. A 9% and 11% improvement was seen in peak oxygen consumption for the SAE and BE, respectively. For peak ventilation, a 23% and 11% improvement was seen for the SAE and BE, respectively. For the ACE, a 16% increase in peak ventilation was seen, with no improvement in aerobic capacity. Total work capacity on the BE was improved by 29% following training. Positive improvements were also seen in isokinetic leg strength. This study demonstrated that a man still suffering residual symptoms following an incidence of GBS was able to improve his cardiopulmonary and work capacity and isokinetic strength of his legs following a supervised training program using the SAE. The subject also reported improvements in activities of daily living.

An in vivo model for the identification of serum proteins in the acquired subgingival pellicle.

The present study describes an in vivo model for the collection of the subgingival pellicle adsorbed to tooth surface, and the identification of some serum proteins within this layer. Clean dentin slabs were prepared from freshly extracted teeth, and then placed subgingivally for 2 h. The dentin slabs with their adsorbed pellicle layer were processed for transmission electron microscopy. Thin sections were made from the specimens, and treated with antisera to human immunoglobulins and albumin. The reactions were visualized by means of protein A-gold complex, which allowed semiquantification of the serum proteins. The indicator proteins were all identified within the pellicle material, but their amounts and distribution varied. Albumin demonstrated higher amounts in the pellicle layer than other proteins, followed by IgA, IgG, and IgM in descending order. The model described seems useful for studying the acquired subgingival pellicle under varying degrees of disease and health.

Attachment of human gingival fibroblasts to planed root surfaces exposed to human plasma in vitro.

We studied the effect of exposing planed dentin surfaces (DS) to human plasma on the attachment of human gingival fibroblasts (HGF) in vitro as compared with their attachment to citric-acid-demineralized DS. Sixty-six DS were prepared from root-planed roots of surgically extracted human third molars. In a pilot experiment 30 DS were demineralized in citric acid (pH 1.0 for 3 min), and each of 3 DS were placed in a culture dish and incubated with fresh plasma for 0, 10, or 30 sec, 1, 10, or 30 min, or 1, 1.5, 2, or 4h. In a second experiment, three culture dishes containing three DS each were assigned to each of four groups. These were untreated (control), incubated with plasma for 2h, acid-demineralized only, or acid-demineralized and then incubated with plasma for 2h. To each dish was added 0.2 X 10(6) HGF, and these were incubated for 2, 6, or 24 h. The unattached cells were then removed, and the DS fixed and processed for SEM. The results showed that exposing demineralized dentin surfaces to plasma causes the absorption of a coating layer, presumably of organic nature, as early as 30 sec after exposure. Acid-demineralized DS alone or together with plasma treatment enhanced both the attachment and the growth of HGF. However, treatment with plasma alone seemed to enhance the HGF attachment less than did acid demineralization alone.

Radiographic quantification of alveolar bone level changes. Predictors of longitudinal bone loss.

The purpose of the present study was to determine the relative importance of a set of predictors for the radiographic change in alveolar bone level over 2 years in a group of 180 subjects and to assess the fit of the applied multivariate model. The included predictors were age, sex, initial bone level, type of initial lesion, tooth type, proximal tooth surface, calculus, and the presence of metal crowns or proximal fillings. The multivariate method of choice was multiple classification analysis. The results indicated that in descending order tooth type, initial bone level, and age were the most important predictors. Sex, calculus, and crown and filling margins also showed significant direct effects (beta) on longitudinal bone loss (p less than 0.05). However, their relative importance was far less than that of tooth type, initial bone level, and age. Proximal side showed no significant direct effect. Using seven predictors, the applied multivariate model explained 20% of the variance in longitudinal bone loss.

Radiographic quantification of alveolar bone level changes. Comparison of 3 currently used methods.

Radiographic bone level changes over 2 years were assessed by 1 absolute and 2 relative techniques in a group of 180 subjects (age 18-68 years, mean 46.7). The absolute technique measured the CEJ-AC distance (mm). The Schei and Björn techniques employed rulers which expressed the alveolar bone level as a % of the root and tooth length, respectively. The applicability and readability of the 3 techniques were compared and their interrelationship evaluated. The absolute technique showed significantly better readability than did both the relative methods (p less than 0.0005), while the Schei technique exhibited the highest ability in detecting the radiographic change in bone level. The correlation between the measurements of bone level change made by the absolute and Schei techniques (r = 0.87) was far better than that between the other techniques (r = 0.56, 0.59).

Effectiveness of Veadent as a plaque-inhibiting mouthwash.

The aim of this study was to compare the effect of the commercially available Veadent mouthwash and chlorhexidine on plaque formation. Plaque accumulating during two 5-day periods was recorded in a group of 10 students. During the experimental periods, the test subjects abstained from mechanical cleaning of the teeth, and chewed sucrose-containing chewing gum every 4th h in order to enhance plaque formation. They also rinsed with either chlorhexidine or Veadent twice a day according to the manufacturer's recommendations. Chlorhexidine mouthrinses resulted in significantly lower plaque scores than did Veadent in the present short-term model study.

Comparison between standardized periapical and bitewing radiographs in assessing alveolar bone loss.

Readability and alveolar bone level were compared in 455 sets of standardized radiographs each consisting of four periapical (PA) and two bitewing (BW) films. BW radiographs showed significantly higher proportions of unreadable sites in the canines and the mesial surface of first premolars (P less than 0.0001), while PA radiographs exhibited significantly higher proportions of unreadable sites in the distal surface of second molars (P less than 0.0001). Alveolar bone level was assessable in a total of 10016 sites, and the comparison showed identical readings in 82% of the sites. In the maxilla, a significantly higher proportion of sites exhibited larger bone loss measurements (P less than 0.0001) and more sites with significantly higher mean values (P less than 0.005) in BW than in PA films. Mandibular sites showed the opposite trend. The majority of the sites revealed a Pearson's correlation coefficient (r) ranging between 0.60 and 0.82. No significant difference between mean bone loss measurements in the two types of radiographs for all the sites was found. It was concluded that the two radiographic techniques may be used interchangeably in epidemiologic studies.